Download Year 10 Science Chemistry Examination November 2011 Part A

Year 10 Science Chemistry
Examination November 2011
Part A Multiple Choice
Answer these questions on the multiple choice answer sheet provided
2
Isotopes have been found as variations of atoms. Which of the following best describes isotopes?
A.
B.
C.
D.
They have different numbers of protons
They have different numbers of neutrons
They have different numbers of electrons
They have different electron shells
3
An element has an atomic number of 16. Which of the following describes its position in the
periodic table?
A.
B.
C.
D.
Period 2 group 6
Period 6 group 2
Period 3 group 6
Period 6 group 3
4
The modern periodic table is based on the increasing number of:A.
B.
C.
D.
Neutrons
Protons
Electrons
Morons
5
Which of the following best describes an element that is a metal?
A.
B.
C.
D.
Small number of valence electrons, good conductor, tends to make cations in a reaction.
Large number of valence electrons, good conductor, tends to make cations in a reaction.
Small number of valence electrons, good conductor, tends to make anions in a reaction.
Small number of valence electrons, poor conductor, tends to make cations in a reaction.
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Year 10 Science Chemistry
Examination November 2011
Part A Multiple Choice
6
Aluminium metal can react with chlorine to make a compound. Which of these describes what
happened to the Aluminium.
A.
B.
C.
D.
It lost 2 electrons to make a cation with a charge of +2
It lost 3 electrons to make a cation with a charge of +3
It gained 3 electrons to make a cation with a charge of +3
It lost 3 electrons to make a anion with a charge of -3
7
When carbon reacts with oxygen to make a compound:A.
B.
C.
D.
It loses 4 electrons to each oxygen atom to make double ionic bonds
It shares 2 electrons with each oxygen atom to make covalent bonds
It shares 4 electrons with each oxygen atom to make double covalent bonds
It gains 4 electrons from each oxygen atom to make double ionic bonds
8
The correct way to write the formula for Aluminium Sulphate is:
A.
B.
C.
D.
Al SO4
Al3 (SO4)2
Al 2 SO4 3
Al2 (SO4)3
9
Which of the following shows the correct balanced equation for the reaction between copper
nitrate and sodium carbonate?
Cu NO3
 Cu CO3 (s)
+ 2 Na NO3 (aq)
 Cu CO3 (aq)
+ 2 Na NO3 (s)
Cu (NO3) 2 (aq) + Na2 CO3(aq)
 Cu CO3 (s)
+ 2 Na NO3 (aq)
Cu (NO3)2 (aq) + Na2 CO3(aq)
 Cu CO3 (aq)
+ 2 Na NO3 (aq)
(aq)
Cu (NO3)2
+ Na CO3(aq)
(aq)
+ Na2 CO3(aq)
2
Year 10 Science Chemistry
Examination November 2011
Part A Multiple Choice
10
Which of the reactions shown below is a single displacement reaction?
A.
B.
C.
D.
AgNO3
CuCO3
Mg
+
CH3OH
+
NaCl

CuO
CuSO4
+
2O2

+


AgCl
CO2
Cu
CO2
+
NaNO3
+
+
MgSO4
2H2O
11
Which of the equations shown below for the combustion of pentane is correctly balanced?
A.
B.
C.
D.
C5H12
C5H12
C5H12
C5H12
+
+
+
+
11O2
O2
8O2
5O2




5CO2
CO2
5CO2
5CO2
+
+
+
+
12H2O
H2O
6H2O
6H2O
12
Which pair of the ionic solutions shown below will produce a precipitate when they are mixed.
A.
B.
C.
D.
Sodium sulphate and copper chloride
Copper nitrate and potassium carbonate
Zinc nitrate and sodium chloride
Aluminium Chloride and copper nitrate
13
Fred has been doing an experiment to test the law of conservation of mass. He heated steel wool
(iron metal) carefully in a crucible. He weighed the crucible before and after the reaction which is
shown by the equation below.
4Fe(s) +
A.
B.
C.
D.
3O2 (g) 
2Fe2O3(s)
There will be no change in the weight of the crucible
There will be a decrease in the weight of the crucible
There will be an increase in the weight of the crucible
He proved that the law of conservation is incorrect
3
Year 10 Science Chemistry
Examination November 2011
Question 1
Part B written
(4 marks)
An unknown element has the symbol
33
15X.
a) What is the atomic number for this element?
b) What is the mass number for this element?
c) How many electrons does the atom for this element have?
d) Draw a diagram to show the electron structure for this element.
Question 2
(4 marks)
Use electron dot diagrams, showing only outer shells, to draw diagrams of the following molecules.
a) Water
H2O
b) Carbon Dioxide
CO2
c) Nitrogen
N2
d) Methane
CH4
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Year 10 Science Chemistry
Examination November 2011
Part B written
Question 3
(2 marks)
Draw diagrams, using electron shells, to show how an atom of Sodium can react with an atom of
Fluorine to make Sodium Fluoride.
Question 4
Write balanced formula for the following ionic compounds.
(4 marks)
a) Sodium Chloride
b) Magnesium Oxide
c) Potassium Sulphate
d) Ammonium Phosphate
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Year 10 Science Chemistry
Examination November 2011
Part B written
Question 5
(4 marks)
Write balanced equations, using symbols, to show each of the following reactions.
a) Decomposition of Copper Carbonate.
b) Combustion of Ethanol (CH3CH2OH)
c) Single displacement of Copper metal with Silver Nitrate solution.
d) Combination reaction of Magnesium metal with Oxygen gas.
Question 6
(4 marks)
Use the table of solubility provided to answer questions about which of the reactions below will
produce a precipitate.
Reaction 1
Copper Sulphate
+
Ammonium Nitrate
Reaction 2
Silver Nitrate
+
Potassium Chloride
Reaction 3
Magnesium Chloride
+
Sodium Chloride
a) Which reaction produces a precipitate?
b) Write the correct formula for the precipitate.
c) Write a balanced symbol equation for the reaction that produces the precipitate.
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Year 10 Science Chemistry
Examination November 2011
Part B written
Question 9
The following equations are unbalanced, although the formulas are correct.
Balance the equations by putting the correct coefficient in the boxes.
C2H4
+
O2

CO2
CO
+
O2

CO2
Al
+
Fe2O3

CO2
+
H2O

+
H2O
Fe
+
Al2O3
C6H12O6
+
O2
Question 10
(4 marks)
(6 marks)
The periodic table was developed by Mendeleev to help organize the elements. Discuss the
periodic table to show your understanding of it by answering the following questions.
a) What is special about the Noble Gases and why do they not react with other elements?
b) What is meant by period and group?
c) How do they relate to electron shells?
d) Which part do the periodic table do metals belong in?
e) What is special about the electrons for metals?
f)
Why do all elements in group 7, (the Halogens), have similar properties?
g) Carbon has two isotopes. What are isotopes?
h) Why are the chemical properties of isotopes similar?
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